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GB.GetBettiMatrix

Syntax

GB.GetBettiMatrix(M:IDEAL or MODULE):TAGGED("$io.Matrix")
    

Summary

returns the Betti matrix computed so far

Description

This function, if used after executing Res(M), prints the Betti matrix for M. Within the Interactive Groebner Framework, in which resolutions may be computed one step at a time, the function returns the Betti matrix for the part of the resolution computed so far. See GB.GetRes for an example.

example

    
Use R ::= Q[t,x,y,z];
I := Ideal(x^2-yt,xy-zt,xy);
Res(I);
0 --> R^2(-5) --> R^4(-4) --> R^3(-2)
-------------------------------
GB.GetBettiMatrix(I);
--------------
               
--------------
   0    0    0 
   0    0    3 
   0    0    0 
   0    4    0 
   2    0    0 
--------------

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See Also